Field
The present disclosure relates generally to communication systems, and more particularly, to dynamically conveyance of information regarding demodulation reference signal (DM-RS) and phase noise compensation reference signal (PC-RS).
Background
Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources. Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems.
These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. An example telecommunication standard is Long Term Evolution (LTE). LTE is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by Third Generation Partnership Project (3GPP). LTE is designed to support mobile broadband access through improved spectral efficiency, lowered costs, and improved services using OFDMA on the downlink, SC-FDMA on the uplink, and multiple-input multiple-output (MIMO) antenna technology. However, as the demand for mobile broadband access continues to increase, there exists a need for further improvements in LTE technology. These improvements may also be applicable to other multi-access technologies and the telecommunication standards that employ these technologies.
DM-RS symbols may be inserted in physical downlink shared channel (PDSCH) or physical uplink shared channel (PUSCH) for channel estimation. Data may be decoded after decoding the DM-RS symbols. It may be preferable to insert DM-RS symbols in the beginning of the PDSCH/PUSCH from a latency perspective. However, in a fast time varying channel, estimated channel may become redundant or invalid for data carried near the end of PDSCH/PUSCH if DM-RS symbols are placed at the beginning of PDSCH/PUSCH.